BioActivities of Coturnix japonica (quail) egg yolk and albumen against physiological stress

Recent Advances in Applications of Bioactive Egg Compounds in Nonfood Sectors

Egg, a highly nutritious food, contains high-quality proteins, vitamins, and minerals. This food has been reported for its potential pharmacological properties, including antibacterial, anti-cancer, anti-inflammatory, angiotensin-converting enzyme (ACE) inhibition, immunomodulatory effects, and use in tissue engineering applications. The significance of eggs and their components in disease prevention and treatment is worth more attention. Eggs not only have been known as a "functional food" to combat diseases and facilitate the promotion of optimal health, but also have numerous industrial applications. The current review focuses on different perceptions and non-food applications of eggs, including cosmetics. The versatility of eggs from an industrial perspective makes them a potential candidate for further exploration of several novel components.

Bioactive Minor Egg Components

In the last 15 years, the development of functional genomics has increased the number of egg proteins identified from 50 to about 1300. These proteins are initially present in eggs to support a harmonious embryonic development. Consequently, this closed embryonic chamber contains molecules exhibiting diverse functions, including defense, nutrition and many predicted biological activities, which have been investigated using both bioinformatics and experimental investigations. In this chapter, we focus on some very interesting activities of high potential reported for minor egg proteins (excluding ovalbumin, ovotransferrin and lysozyme). The shell matrix proteins are involved in the calcification process to define and control the final texture of the shell and thereby its mechanical properties. Antimicrobial proteins are part of innate immunity and are mainly present in the white and vitelline membranes. They encompass several protein families, including protease inhibitors, vitamin-binding proteins, defensins, LBP-PLUNC family proteins and heparin-binding proteins. The egg also possesses additional bioactive proteins with direct anti-cancerous and antioxidant activities or whose biochemical properties are currently used to develop diagnostic tools and strategies for targeted therapy. Finally, this chapter also reports some emerging functions in tissue remodeling/wound healing and proposes some relevant bioactive candidates and research fields that would be interesting to investigate further.

Regulation of lipid peroxidation and ferroptosis in diverse species

This review by Conrad et al. reviews the functions and regulation of lipid peroxidation, ferroptosis, and the antioxidant network in diverse species, including humans, other mammals and vertebrates, plants, invertebrates, yeast, bacteria, and archaea, and discusses the potential evolutionary roles of lipid peroxidation and ferroptosis.

Lipid peroxidation is the process by which oxygen combines with lipids to generate lipid hydroperoxides via intermediate formation of peroxyl radicals. Vitamin E and coenzyme Q₁₀ react with peroxyl radicals to yield peroxides, and then these oxidized lipid species can be detoxified by glutathione and glutathione peroxidase 4 (GPX4) and other components of the cellular antioxidant defense network. Ferroptosis is a form of regulated nonapoptotic cell death involving overwhelming iron-dependent lipid peroxidation. Here, we review the functions and regulation of lipid peroxidation, ferroptosis, and the antioxidant network in diverse species, including humans, other mammals and vertebrates, plants, invertebrates, yeast, bacteria, and archaea. We also discuss the potential evolutionary roles of lipid peroxidation and ferroptosis.

Quail (Coturnix japonica) egg yolk bioactive components attenuate streptozotocin-induced testicular damage and oxidative stress in diabetic rats

INTRODUCTION

The testicular milieu is the machinery for the metabolism of testosterone in the male reproductive system.

PURPOSE

The dysfunction of this highly regenerating system is inevitable in the condition of glucose imbalance as a result of insulin machinery impairment. Therefore, it is imperative to recommend dietary intervention for attenuating the testicular dysfunction and oxidative stress resulting from STZ-induction of diabetes.

METHODS

STZ-induced diabetes (65 mg/kg, ip) was treated with QEYEM (50, 100 and 200 mg/kg/day) and quercetin (50 mg/kg/day) for 7weeks. In serum, glucose, testosterone, IL-6 and TNF-α levels were estimated, and in testis, tissues TBARS, sulfhydryl groups, nucleic acids and total protein (TP) levels were estimated. SOD, CAT and GST activities were also determined in testicular cells. Histopathological changes were evaluated in a cross-section of testis.

RESULTS

Testosterone concentration was decreased while pro-inflammatory markers were increased in STZ-assaulted rats. Treatment using QEYEM of diabetic rats corrected assaults and reverse significantly the diabetic conditions. QEYEM-treated groups showed significant inhibition of TBARS levels and elevation of testicular GSH, NP-SH, total protein (TP) and nucleic acids-DNA and RNA levels. The QEYEM administration reversed the inhibited activities of SOD, CAT and GST in testicular cells in diabetic rats. The characterization of the extract carried out through HPLC analytical techniques revealed vitamins A, D and E concentrations of 0.645, 0.012 and 6.3 mg/100 g, respectively.

CONCLUSION

QEYEM supplementation to STZ-induced diabetic rats for seven (7) consecutive weeks is a potential intervention against testicular damage in adult diabetic rats, probably by decreasing oxidative stress.